Unknown type name 'IRsend' - arduino

Question

In the C file in simplesample_mqtt.c, which connects Arduino to the Azure IoT hub, I need to use the IRsend and IrRemoteESP8266 libraries to send an infrared signal with Azure IoT hub.
#include <IRremoteESP8266.h>
#include <IRsend.h>
IRsend irsend(10); // An IR LED is controlled by GPIO pin 4 (D2)
I don't have any problem when I use this code in my main Ardunio file. But when I use these includes in a C file (implesample_mqtt.c), I get this error from line 3: "unknown type name 'IRsend'".
error full info :
Arduino: 1.8.2 (Windows 10), Board: "NodeMCU 0.9 (ESP-12 Module), 80 MHz, 115200, 4M (3M SPIFFS)"
In file included from sketch\simplesample_mqtt.c:29:0:
C:\Program Files (x86)\Arduino\libraries\IRremoteESP8266\src/IRsend.h:29:1: error: unknown type name 'class'
class IRsend {
C:\Program Files (x86)\Arduino\libraries\IRremoteESP8266\src/IRsend.h:29:14: error: expected '=', ',', ';', 'asm' or 'attribute' before '{' token
class IRsend {
simplesample_mqtt.c:31: error: unknown type name 'IRsend'
IRsend irsend(10); // An IR LED is controlled by GPIO pin 4 (D2)
simplesample_mqtt.c:31: error: expected declaration specifiers or '...' before numeric constant
IRsend irsend(10); // An IR LED is controlled by GPIO pin 4 (D2)
exit status 1
unknown type name 'IRsend'
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Answer 1

I solved this problem. The reason for this is because main ardunio is c++ and simplesample_mqtt.c is c code and we have to use c++ code in c code :
i main ardunio file you have to declare function like this :
extern "C" void TurnOn();
void TurnOn()
{
digitalWrite(RELAY_SONOFF, HIGH);
digitalWrite(LED_SONOFF, HIGH);
}
and use this function in c code :
void TurnOn();
EXECUTE_COMMAND_RESULT TurnOn(ContosoAnemometer* device)
{
(void)device;
TurnOn();
(void)printf("Turning fan on.\r\n");
return EXECUTE_COMMAND_SUCCESS;
}